# CVE-2022-30698: Novel "ghost domain names" attack by introducing subdomain delegations

> Attackers can keep rogue domains resolvable by exploiting delegation cache updates, bypassing domain revocation mechanisms in Unbound DNS resolver.

- **Severity:** Medium 6.5 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 1 Aug 2022
- **Updated:** 16 Sep 2024
- **Also known as:** ALPINE-CVE-2022-30698, AZL-10452, DEBIAN-CVE-2022-30698, GHSA-297v-qp46-84h5, UBUNTU-CVE-2022-30698, openSUSE-SU-2024:12235-1

## What is CVE-2022-30698?

CVE-2022-30698 is a medium-severity vulnerability in Fedoraproject Fedora, published on 1 Aug 2022. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

NLnet Labs Unbound, up to and including version 1.16.1 is vulnerable to a novel type of the "ghost domain names" attack. The vulnerability works by targeting an Unbound instance. Unbound is queried for a subdomain of a rogue domain name. The rogue nameserver returns delegation information for the subdomain that updates Unbound's delegation cache. This action can be repeated before expiry of the delegation information by querying Unbound for a second level subdomain which the rogue nameserver provides new delegation information. Since Unbound is a child-centric resolver, the ever-updating child delegation information can keep a rogue domain name resolvable long after revocation. From version 1.16.2 on, Unbound checks the validity of parent delegation records before using cached delegation information.

Weakness: CWE-613 (DEPRECATED: Insufficient Session Expiration)

## Which versions are affected by CVE-2022-30698?

It affects 2 products.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `unbound` | openSUSE:Tumbleweed | All versions | 1.16.2-1.1 |

Products: Fedoraproject Fedora, Nlnetlabs Unbound.

## How do I fix CVE-2022-30698?

Upgrade to a fixed version.

## Is CVE-2022-30698 being exploited?

There is no known exploitation of CVE-2022-30698 in the wild and no public exploit code.

## Other vulnerabilities in Fedoraproject Fedora

- [CVE-2024-4577](https://insights.sbomify.com/CVE-2024-4577/): PHP-CGI OS Command Injection (critical 9.8, exploited in the wild)
- [CVE-2021-39226](https://insights.sbomify.com/CVE-2021-39226/): Grafana Authentication Bypass (critical 9.8, exploited in the wild)
- [CVE-2019-5544](https://insights.sbomify.com/CVE-2019-5544/): VMware ESXi and Horizon DaaS OpenSLP Heap-Based Buffer Overflow (critical 9.8, exploited in the wild)
- [CVE-2024-4947](https://insights.sbomify.com/CVE-2024-4947/): Google Chromium V8 Type Confusion (critical 9.6, exploited in the wild)
- [CVE-2024-4671](https://insights.sbomify.com/CVE-2024-4671/): Google Chromium Visuals Use-After-Free (critical 9.6, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2022-30698 and fix it if it is affected.

What it is: CVE-2022-30698 is a medium-severity vulnerability in Fedoraproject Fedora, published on 1 Aug 2022. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2022-30698 in the wild and no public exploit code.

Affected product: Fedoraproject Fedora. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2022-30698/ (Markdown: https://insights.sbomify.com/CVE-2022-30698/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2022-30698
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2022-30698
- OSV: https://osv.dev/vulnerability/CVE-2022-30698

---
From sbomify Insights: https://insights.sbomify.com/CVE-2022-30698/
Summaries are generated and may contain mistakes; the official description above is the record.